for a day or two after our visit from the fake asylum attendant i was in some hopes that he might return, and i refused to leave the flat even for a moment. as far as i could see, he had no reason to suspect that we had penetrated his disguise. he might, i thought, return and try to remove the body, but poirot scoffed at my reasoning.

"mon ami," he said, "if you wish you may wait in to put salt on the little bird's tail, but for me i do not waste my time so."

"well then, poirot," i argued, "why did he run the risk of coming at all. if he intended to return later for the body, i can see some point in his visit. he would at least be removing the evidence against himself; as it is, he does not seem to have gained anything."

poirot shrugged his most gallic shrug. "but you do not see with the eyes of number four, hastings," he said. "you talk of evidence, but what evidence have we against him? true, we have a body, but we have no proof even that the man was murdered—prussic acid, when inhaled, leaves no trace. again, we can find no one who saw any one enter the flat during our absence, and we have found out nothing about the movements of our late friend, mayerling....

"no, hastings, number four has left no trace, and he knows it. his visit we may call a reconnaissance. perhaps he wanted to make quite sure that mayerling was dead, but more likely, i think, he came to see hercule poirot, and to have speech with the adversary whom alone he must fear."

poirot's reasoning appeared to me typically egotistical, but i forbore to argue.

"and what about the inquest?" i asked. "i suppose you will explain things clearly there, and let the police have a full description of number four."

"and to what end? can we produce anything to impress a coroner's jury of your solid britishers? is our description of number four of any value? no; we shall allow them to call it 'accidental death,' and may be, although i have not much hope, our clever murderer will pat himself on the back that he deceived hercule poirot in the first round."

poirot was right as usual. we saw no more of the man from the asylum, and the inquest, at which i gave evidence, but which poirot did not even attend, aroused no public interest.

as, in view of his intended trip to south america, poirot had wound up his affairs before my arrival, he had at this time no cases on hand, but although he spent most of his time in the flat i could get little out of him. he remained buried in an arm-chair, and discouraged my attempts at conversation.

and then one morning, about a week after the murder, he asked me if i would care to accompany him on a visit he wished to make. i was pleased, for i felt he was making a mistake in trying to work things out so entirely on his own, and i wished to discuss the case with him. but i found he was not communicative. even when i asked where we were going, he would not answer.

poirot loves being mysterious. he will never part with a piece of information until the last possible moment. in this instance, having taken successively a 'bus and two trains, and arrived in the neighbourhood of one of london's most depressing southern suburbs, he consented at last to explain matters.

"we go, hastings, to see the one man in england who knows most of the underground life of china."

"indeed! who is he?"

"a man you have never heard of—a mr. john ingles. to all intents and purposes, he is a retired civil servant of mediocre intellect, with a house full of chinese curios with which he bores his friends and acquaintances. nevertheless, i am assured by those who should know that the only man capable of giving me the information i seek is this same john ingles."

a few moments more saw us ascending the steps of the laurels, as mr. ingles's residence was called. personally, i did not notice a laurel bush of any kind, so deduced that it had been named according to the usual obscure nomenclature of the suburbs.

we were admitted by an impassive-faced chinese servant and ushered into the presence of his master. mr. ingles was a squarely-built man, somewhat yellow of countenance, with deep-set eyes that were oddly reflective in character. he rose to greet us, setting aside an open letter which he had held in his hand. he referred to it after his greeting.

"sit down, won't you? halsey tells me that you want some information and that i may be useful to you in the matter."

"that is so, monsieur. i ask of you if you have any knowledge of a man named li chang yen?"

"that's rum—very rum indeed. how did you come to hear about the man?"

"you know him, then?"

"i've met him once. and i know something of him—not quite as much as i should like to. but it surprises me that any one else in england should even have heard of him. he's a great man in his way—mandarin class and all that, you know—but that's not the crux of the matter. there's good reason to suppose that he's the man behind it all."

"behind what?"

"everything. the world-wide unrest, the labour troubles that beset every nation, and the revolutions that break out in some. there are people, not scaremongers, who know what they are talking about, and they say that there is a force behind the scenes which aims at nothing less than the disintegration of civilisation. in russia, you know, there were many signs that lenin and trotsky were mere puppets whose every action was dictated by another's brain. i have no definite proof that would count with you, but i am quite convinced that this brain was li chang yen's."

"oh, come," i protested, "isn't that a bit farfetched? how would a chinaman cut any ice in russia?"

poirot frowned at me irritably.

"for you, hastings," he said, "everything is farfetched that comes not from your own imagination; for me, i agree with this gentleman. but continue, i pray, monsieur."

"what exactly he hopes to get out of it all i cannot pretend to say for certain," went on mr. ingles; "but i assume his disease is one that has attacked great brains from the time of akbar and alexander to napoleon—a lust for power and personal supremacy. up to modern times armed force was necessary for conquest, but in this century of unrest a man like li chang yen can use other means. i have evidence that he has unlimited money behind him for bribery and propaganda, and there are signs that he controls some scientific force more powerful than the world has dreamed of."

poirot was following mr. ingles's words with the closest attention.

"and in china?" he asked. "he moves there too?"

the other nodded in emphatic assent.

"there," he said, "although i can produce no proof that would count in a court of law, i speak from my own knowledge. i know personally every man who counts for anything in china to-day, and this i can tell you: the men who loom most largely in the public eye are men of little or no personality. they are marionettes who dance to the wires pulled by a master hand, and that hand is li chang yen's. his is the controlling brain of the east to-day. we don't understand the east—we never shall; but li chang yen is its moving spirit. not that he comes out into the limelight—oh, not at all; he never moves from his palace in pekin. but he pulls strings—that's it, pulls strings—and things happen far away."

"and is there no one to oppose him?" asked poirot.

mr. ingles leant forward in his chair.

"four men have tried in the last four years," he said slowly; "men of character, and honesty, and brain power. any one of them might in time have interfered with his plans." he paused.

"well?" i queried.

"well, they are dead. one wrote an article, and mentioned li chang yen's name in connection with the riots in pekin, and within two days he was stabbed in the street. his murderer was never caught. the offences of the other two were similar. in a speech or an article, or in conversation, each linked li chang yen's name with rioting or revolution, and within a week of his indiscretion each was dead. one was poisoned; one died of cholera, an isolated case—not part of an epidemic; and one was found dead in his bed. the cause of the last death was never determined, but i was told by a doctor who saw the corpse that it was burnt and shrivelled as though a wave of electrical energy of incredible power had passed through it."

"and li chang yen?" inquired poirot. "naturally nothing is traced to him, but there are signs, eh?"

mr. ingles shrugged.

"oh, signs—yes, certainly. and once i found a man who would talk, a brilliant young chinese chemist who was a protégé of li chang yen's. he came to me one day, this chemist, and i could see that he was on the verge of a nervous breakdown. he hinted to me of experiments on which he'd been engaged in li chang yen's palace under the mandarin's direction—experiments on coolies in which the most revolting disregard for human life and suffering had been shown. his nerve had completely broken, and he was in the most pitiable state of terror. i put him to bed in a top room of my own house, intending to question him the next day—and that, of course, was stupid of me."

"how did they get him?" demanded poirot.

"that i shall never know. i woke that night to find my house in flames, and was lucky to escape with my life. investigation showed that a fire of amazing intensity had broken out on the top floor, and the remains of my young chemist friend were charred to a cinder."

i could see from the earnestness with which he had been speaking that mr. ingles was a man mounted on his hobby horse, and evidently he, too, realised that he had been carried away, for he laughed apologetically.

"but, of course," he said, "i have no proofs, and you, like the others, will merely tell me that i have a bee in my bonnet."

"on the contrary," said poirot quietly, "we have every reason to believe your story. we ourselves are more than a little interested in li chang yen."

"very odd your knowing about him. didn't fancy a soul in england had ever heard of him. i'd rather like to know how you did come to hear of him—if it's not indiscreet."

"not in the least, monsieur. a man took refuge in my rooms. he was suffering badly from shock, but he managed to tell us enough to interest us in this li chang yen. he described four people—the big four—an organisation hitherto undreamed of. number one is li chang yen, number two is an unknown american, number three an equally unknown frenchwoman, number four may be called the executive of the organisation—the destroyer. my informant died. tell me, monsieur, is that phrase known to you at all? the big four."

"not in connection with li chang yen. no, i can't say it is. but i've heard it, or read it, just lately—and in some unusual connection too. ah, i've got it."

he rose and went across to an inlaid lacquer cabinet—an exquisite thing, as even i could see. he returned with a letter in his hand.

"here you are. note from an old sea-faring man i ran against once in shanghai. hoary old reprobate—maudlin with drink by now, i should say. i took this to be the ravings of alcoholism."

he read it aloud:—

"dear sir,—you may not remember me, but you did me a good turn once in shanghai. do me another now. i must have money to get out of the country. i'm well hid here, i hope, but any day they may get me. the big four, i mean. it's life or death. i've plenty of money, but i daren't get at it, for fear of putting them wise. send me a couple of hundred in notes. i'll repay it faithful—i swear to that.—your servant, sir,

"jonathan whalley."

"dated from granite bungalow, hoppaton, dartmoor. i'm afraid i regarded it as rather a crude method of relieving me of a couple of hundred which i can ill spare. if it's any use to you—" he held it out.

"je vous remercie, monsieur. i start for hoppaton à l'heure même."

"dear me, this is very interesting. supposing i come along too? any objection?"

"i should be charmed to have your company, but we must start at once. we shall not reach dartmoor until close on nightfall, as it is."

john ingles did not delay us more than a couple of minutes, and soon we were in the train moving out of paddington bound for the west country. hoppaton was a small village clustering in a hollow right on the fringe of the moorland. it was reached by a nine-mile drive from moretonhamstead. it was about eight o'clock when we arrived; but as the month was july, the daylight was still abundant.

we drove into the narrow street of the village and then stopped to ask our way of an old rustic.

"granite bungalow," said the old man reflectively, "it be granite bungalow you do want? eh?"

we assured him that this was what we did want.

the old man pointed to a small gray cottage at the end of the street.

"there be t'bungalow. do yee want to see t'inspector?"

"what inspector?" asked poirot sharply; "what do you mean?"

"haven't yee heard about t'murder, then? a shocking business t'was seemingly. pools of blood, they do say."

"mon dieu!" murmured poirot. "this inspector of yours, i must see him at once."

five minutes later we were closeted with inspector meadows. the inspector was inclined to be stiff at first, but at the magic name of inspector japp of scotland yard, he unbent.

"yes, sir; murdered this morning. a shocking business. they 'phoned to moreton, and i came out at once. looked a mysterious thing to begin with. the old man—he was about seventy, you know, and fond of his glass, from all i hear—was lying on the floor of the living-room. there was a bruise on his head and his throat was cut from ear to ear. blood all over the place, as you can understand. the woman who cooks for him, betsy andrews, she told us that her master had several little chinese jade figures, that he'd told her were very valuable, and these had disappeared. that, of course, looked like assault and robbery; but there were all sorts of difficulties in the way of that solution. the old fellow had two people in the house; betsy andrews, who is a hoppaton woman, and a rough kind of man-servant, robert grant. grant had gone to the farm to fetch the milk, which he does every day, and betsy had stepped out to have a chat with a neighbour. she was only away twenty minutes—between ten and half-past—and the crime must have been done then. grant returned to the house first. he went in by the back door, which was open—no one locks up doors round here—not in broad daylight, at all events—put the milk in the larder, and went into his own room to read the paper and have a smoke. had no idea anything unusual had occurred—at least, that's what he says. then betsy comes in, goes into the living-room, sees what's happened, and lets out a screech to wake the dead. that's all fair and square. some one got in whilst those two were out, and did the poor old man in. but it struck me at once that he must be a pretty cool customer. he'd have to come right up the village street, or creep through some one's back yard. granite bungalow has got houses all round it, as you can see. how was it that no one had seen him?"

the inspector paused with a flourish.

"aha, i perceive your point," said poirot. "to continue?"

"well, sir, fishy, i said to myself—fishy. and i began to look about me. those jade figures, now. would a common tramp ever suspect that they were valuable? anyway, it was madness to try such a thing in broad daylight. suppose the old man had yelled for help?"

"i suppose, inspector," said mr. ingles, "that the bruise on the head was inflicted before death?"

"quite right, sir. first knocked him silly, the murderer did, and then cut his throat. that's clear enough. but how the dickens did he come or go? they notice strangers quick enough in a little place like this. it came to me all at once—nobody did come. i took a good look round. it had rained the night before, and there were footprints clear enough going in and out of the kitchen. in the living-room there were two sets of footprints only (betsy andrews' stopped at the door)—-mr. whalley's (he was wearing carpet slippers) and another man's. the other man had stepped in the blood-stains, and i traced his bloody footprints—i beg your pardon, sir."

"not at all," said mr. ingles, with a faint smile; "the adjective is perfectly understood."

"i traced them to the kitchen—but not beyond. point number one. on the lintel of robert grant's door was a faint smear—a smear of blood. that's point number two. point number three was when i got hold of grant's boots—which he had taken off—and fitted them to the marks. that settled it. it was an inside job. i warned grant and took him into custody; and what do you think i found packed away in his portmanteau? the little jade figures and a ticket-of-leave. robert grant was also abraham biggs, convicted for felony and housebreaking five years ago."

the inspector paused triumphantly.

"what do you think of that, gentlemen?"

"i think," said poirot, "that it appears a very clear case—of a surprising clearness, in fact. this biggs, or grant, he must be a man very foolish and uneducated, eh?"

"oh, he is that—a rough, common sort of fellow. no idea of what a footprint may mean."

"clearly he reads not the detective fiction! well, inspector, i congratulate you. we may look at the scene of the crime. yes?"

"i'll take you there myself this minute. i'd like you to see those footprints."

"i, too, should like to see them. yes, yes, very interesting, very ingenious."

we set out forthwith. mr. ingles and the inspector forged ahead. i drew poirot back a little so as to be able to speak to him out of the inspector's hearing.

"what do you really think, poirot. is there more in this than meets the eye?"

"that is just the question, mon ami. whalley says plainly enough in his letter that the big four are on his track, and we know, you and i, that the big four is no bogey for the children. yet everything seems to say that this man grant committed the crime. why did he do so? for the sake of the little jade figures? or is he an agent of the big four? i confess that this last seems more likely. however valuable the jade, a man of that class was not likely to realise the fact—at any rate, not to the point of committing murder for them. (that, par exemple, ought to have struck the inspector.) he could have stolen the jade and made off with it instead of committing a brutal and quite purposeless murder. ah, yes; i fear our devonshire friend has not used his little gray cells. he has measured footprints, and has omitted to reflect and arrange his ideas with the necessary order and method."